Population dynamics of microfilarial production and eosinophilic levels in slow lorises infected with Breinlia sergenti. Petter (Filarioidea: Dipetalonematidae)

Population dynamics of microfilarial production and eosinophilic levels in slow lorises infected with Breinlia sergenti, Petter (Filarioidea: Dipetalonematidae). International Journal for Parsitology 4: 383388. Observations have been made on microfilarial and eosinophilic levels in slow lorises infected with Breinlia sergenti. Animals given a single inoculation of 100-150 infective larvae exhibited three different patterns of microfilaraemia while superinfected animals showed enhanced microfilarial levels. It appeared that the number of inoculations as well as the interval between inocula are important factors in enhancing microfilarial levels. Two different types of incubation periods were seen, one at 100-120 days and the other at 200 days. The eosinophilic levels were investigated in some of the animals and an attempt was made to correlate these levels with the microfilaraemia. Cortisone injection appeared to promote a vigorous eosinophilia in some of the infected animals tested.     

Apparent Mutagenic Effect of Induction of Lambda Prophage Inserted Between lysA and thyA

Induction of a heat-inducible abnormal lambda prophage inserted between lysA and thyA in Escherichia coli resulted in a number of auxotrophic mutants in the surviving cured-cell populations. These mutants could not be accounted for by deletions arising on formation of lambda hybrid particles carrying regions adjacent to the insertion site. The properties of these mutants, which were almost all spontaneously revertable, have been described and mapped by F′ episome complementation. Tentatively, it was suggested that induction of the lambda lysogen leads to a mutagenic state.     

Autoradiographic and immunofluorescent studies of cytological changes induced inBacillus cereus by chloramphenicol

Autoradiographic and fluorescent antibody techniques were used to study the formation of protrusions on the cell periphery ofBacillus cereus. The cells were grown in a synthetic medium containing chloramphenicol and H³-labelleddl-alanine, and examined at time intervals for cytological changes. One or more protrusions were detected on approximately 4% of the cell population. Active cell-wall synthesis was found to take place in these cells except at the periphery of the protrusions. On this basis it is suggested that the protrusions are not abnormal growing points but represent osmotically fragile zones where cell-wall synthesis has not taken place.The study was supported by a grant from the National Research Council of Canada.